Delegates to a U.N. conference on global warming are working hard in the meeting's final hours to reach a deal on long-term efforts to cut carbon emissions.
The biggest stumbling block is the United States, which rejects the Kyoto Protocol on cutting "greenhouse," or heat-trapping, emissions. Delegates want to extend talks on the accord, which is set to expire in 2012.
The Bush administration says the protocol would hurt the U.S. economy, and says it unfairly exempts developing nations such as China and India.
Former U.S. President Bill Clinton rejected that charge in a surprise talk at the Montreal, Canada, summit on Friday. Mr. Clinton, who endorsed the Kyoto protocols while president, told delegates the accord would not hurt developed nations. He added it was time to stop doubting the effect of these gases, saying "climate change is real."